15 Amazing Sleeping Habits of Animals

Animals don’t have sleeping masks or soothing prerecorded sounds to help them get the sleep they need. They have to make do with what nature and their bodies allow. Consequently, the fauna of planet Earth have found some incredible ways to get their much-needed rest.

1. Dolphins

Dolphins are amazing creatures, and while they are usually noted for their adorableness, wits and/or disturbing sexual aggression, their sleeping habits are worth mentioning too. They can enter into periods of very deep sleep referred to as "logging" because while in it, a dolphin looks like a log floating at the surface of the water. Crazier still, the bottlenose dolphin readies itself for slumber by literally shutting down half of its brain, as well as the eye opposite the powered-down hemisphere. The other half of the brain (and opposite eye) stays turned on to watch out for whatever might come along, whether be it other dolphins or predators. It also tells the dolphin when to come up for air. After two hours or so, the sides switch, so both eyes and brain hemispheres get their due rest. This process isn’t unique to dolphins, as fruit bats, porpoises, iguanas, seals, birds, and ducks do it too.

2. Sperm Whales

In 2008, researchers happened upon a group of sleeping sperm whales bobbing vertically in the water off the coast of northern Chile. The sight alone was amazing, but then things got strange. These whales, which were thought to only allow one side of their brain to rest at a time, like dolphins and some other whales, didn’t seem to notice the approaching vessel. It wasn’t until one of the cetaceans was accidentally nudged that the group woke up and fled. Through this discovery, researchers learned that sperm whales sleep differently from their relatives—in short, regular periods of full sleep near the surface. They don’t breathe or move during their naps, and if this is the only kind of sleep they get (it’s unclear whether they also engage in half-brain sleep), the relatively short amount of cumulative slumber might make them the least sleep-dependent of all mammals.

3. Giraffes

Giraffes don't rest much longer than sperm whales do. They sleep about 20 minutes a day in order to avoid predators. Being such a tall, lanky beast also makes it difficult to catch some quick z’s, but when they do hunker down and curl up, it’s pretty adorable.

4. Sea Otters

Predators aren’t the only issue to navigate while asleep. As otters know, there’s also the possibility of drifting off (pun absolutely intended). When sea otters fall asleep, they do so while lying on their backs at the surface of the water and in groups or in seaweed forests, sometimes holding hands to keep from floating apart.

5. Albatrosses

The albatross is a sea bird that spends much of its life soaring around on the hunt. Its lifestyle doesn’t leave a lot of time for snoozing, so it’s believed the albatross multitasks by sleeping while flying. Alpine swifts are believed to do this too, as are migratory Swainson Thrush birds, who take hundreds of little power naps lasting only a few seconds each.

6. Ducks

Our feathered friends do more than sleep with one eye open. They sleep in a clique. Ducks queue up in a row when it’s time to hit the hay, and the ones at the end of the line keep the eye facing away from the group open to watch out for predators, and close the other. The ducks inside close both of their eyes. Thesingle-hemisphere sleep in the bookending ducks keeps the whole row safe.

7. Meerkats

Meerkats spend their nights in burrows, which consist of complex tunnel systems and underground sleeping quarters. Communities of meerkats are called mobs or gangs and can consist of up to 40 animals with an alpha male and female in each community. They sleep in heaps, getting warmth from one another and protecting the gang leaders at the bottom of the pile. Puppies, squirrels, bats, and a slew of other creatures are also known to huddle up for warmth during sleep (including the elusive homo sapiens).

8. Horses, Zebras, and Elephants

This is the crew of the standing sleepers, who stay alert during their rest by remaining on their feet. These animals are able to lock their legs in a straight standing position in such a way that it doesn’t require much muscle effort. This is called a “stay apparatus.” While it’s a cool trick, horses (and cows too) do need to lie down from time to time, because they can’t achieve REM sleep while standing up. Flamingos sleep while standing too, but they do so because there aren’t many cozy places to slumber in their usual habitats.

9. Brown Bats

On the other side of the mammalian sleep spectrum from sperm whales and giraffes are brown bats, which sleep about 19 hours a day. The nocturnal creatures snooze upside down all day, a stance born of efficiency, as it’s easier for them and their weak wings to take off from that position. After bats, the lengthiest daily sleepers are the armadillo, opossum, sloth, tiger, and then domestic cat. Keep that in mind next time you want to tell your feline to get a job.

10. Sharks

Most sharks have to keep moving constantly in order to get oxygen through their gills, while others have developed spiracles, openings behind the eye that allow them to take in oxygen while stationary. But generally their sleep is thought to be more of an idle state than a full-fledged shut down. Scientists have found that the spiny dogfish’s swimming might be coordinated by the spinal cord and not the brain, which would indicate that sharks might be able to power down their noggins and continue moving after all. Others speculate that some white sharks might face the current while stationary, so water moves over their gills with no effort from the fish itself.

11. Walruses

Walruses can also sleep and swim at the same time and are basically that friend of yours who can fall asleep anywhere. They can hold their breath for up to five minutes and catch a nap underwater and deep sleep ashore for as many as 19 hours. To be fair though, they deserve it, as walruses have been known to swim continuously for up to 84 hours. For water sleeping, walruses can inflate spaces in their bodies called pharyngeal pouches, which act as sort of a biological life jacket to keep the blubbery beasts afloat.

12. Desert Snail

It doesn’t seem like a snail would have a very taxing life, but these little slimy creatures can go on sleeping for literally years. One particularly famous incident involved an Egyptian desert snail who was assumed dead by a British Museum staffer who affixed the snail to an identification card. Four years later, traces of slime were discovered on the card and the shell was put in water, where the animal crawled out.

13. Frogs

Frogs survive winter by hibernating much like their larger, furrier friends, but their feats are arguably way more incredible. Frogs are equipped with a kind of animal antifreeze, which means that while ice crystals may form in body cavities and under the skin, high concentrations of glucose in its vital organs prevents those essential parts from freezing. A partially frozen frog stops breathing and its heart ceases beating, but when the spring thaw comes and temperatures start to rise, its body resumes its functions and springs back to life.

14. Bears

The sleeping habits of bears aren’t usually anything notable, except when it’s time to give birth. In the winter months, when pregnant mothers are deep in hibernation mode, their heart rates are slow, and they’re not eating, drinking, urinating, defecating, or exercising. But mama bears will rouse themselves enough to do a little thing called giving birth. The cubs then nurse on their sleeping mom for the next few months until she wakes up and takes them out into the world.

15. Apes

Scientists are now studying apes to learn things about the way humans sleep and how that might have helped us evolve. They've found that animals like the orangutan, gorilla, and chimpanzee all like to curl up to sleep just like humans. They also make beds or find platforms for predator-free slumber, which consequently helps them sleep better than counterparts such as the upright-sleeping baboon. That chance for a longer, more restful sleep might have been a factor in our own evolutionary process, helping us to get smarter with each 40 winks.

Stakeouts, sonar studies, and a 24-hour video feed have all been set up in an effort to confirm the existence of the legendary Loch Ness Monster. Now, the Associated Press reports that an international team of scientists will use DNA analysis to learn what's really hiding in the depths of Scotland's most mysterious landmark.

The team, led by Neil Gemmell, who researches evolutionary genetics at the University of Otago in New Zealand, will collect 300 water samples from various locations and depths around the lake. The waters are filled with microscopic DNA fragments animals leave behind as they swim, mate, eat, poop, and die in the waters, and if Nessie is a resident, she's sure to leave bits of herself floating around as well.

After extracting the DNA from the organic material found in the water samples, the scientists plan to sequence it. The results will then be compared to the DNA profiles of known species. If there's evidence of an animal that's not normally found in the lake, or an entirely new species, the researchers will hopefully spot it.

Gemmell is a Nessie skeptic, and he says the point of the project isn't necessarily to discover new species. Rather, he wants to create a genetic profile of the lake while generating some buzz around the science behind it.

If the study goes according to plan, the database of Loch Ness's inhabitants should be complete by 2019. And though the results likely won't include a long-extinct plesiosaur, they may offer insights about other invasive species that now call the lake home.

Here in the Americas, lake monster legends are a dime a dozen. More than a few of them were probably inspired by these ancient-looking creatures. In honor of World Turtle Day, here are 10 things you might not have known about snapping turtles.

1. THE COMMON SNAPPING TURTLE IS NEW YORK'S OFFICIAL STATE REPTILE.

Elementary school students voted to appoint Chelydra serpentina in a 2006 statewide election. Weighing as much as 75 pounds in the wild (and 86 in captivity), this hefty omnivore’s natural range stretches from Saskatchewan to Florida.

2. ALLIGATOR SNAPPING TURTLES CAN BE LARGE. (VERY LARGE.)

Utterly dwarfing their more abundant cousin, alligator snappers (genus: Macrochelys) are the western hemisphere’s biggest freshwater turtles. The largest one on record, a longtime occupant of Chicago’s Shedd Aquarium, weighed 249 pounds.

A monstrous 403-pounder was reported in Kansas during the Great Depression, though this claim was never confirmed.

3. COMMON SNAPPERS HAVE LONGER NECKS AND SPIKIER TAILS.

Alligator snappers also display proportionately bigger heads and noses plus a trio of tall ridges atop their shells. Geographically, alligator snapping turtles are somewhat restricted compared to their common relatives, and are limited mainly to the southeast and Great Plains.

4. BOTH VARIETIES AVOID CONTACT WITH PEOPLE.

If given the choice between fight and flight, snapping turtles almost always distance themselves from humans. The animals spend the bulk of their lives underwater, steering clear of nearby Homo sapiens. However, problems can arise on dry land, where the reptiles are especially vulnerable. Females haul themselves ashore during nesting season (late spring to early summer). In these delicate months, people tend to prod and handle them, making bites inevitable.

5. YOU REALLY DON'T WANT TO GET BITTEN BY ONE.

Snapping turtle jaw strength—while nothing to sneeze at—is somewhat overrated. Common snapping turtles can clamp down with up to 656.81 newtons (N) of force, though typical bites register an average of 209 N. Their alligator-like cousins usually exert 158 N. You, on the other hand, can apply 1300 N between your second molars.

Still, power isn’t everything, and neither type of snapper could latch onto something with the crushing force of a crocodile’s mighty jaws. Yet their sharp beaks are well-designed for major-league shearing. An alligator snapping turtle’s beak is capable of slicing fingers clean off and (as the above video proves) obliterating pineapples.

Not impressed yet? Consider the following. It’s often said that an adult Macrochelys can bite a wooden broom handle in half. Intrigued by this claim, biologist Peter Pritchard decided to play MythBuster. In 1989, he prodded a 165-pound individual with a brand new broomstick. Chomp number one went deep, but didn’t quite break through the wood. The second bite, though, finished the job.

6. SCIENTISTS RECENTLY DISCOVERED THAT THERE ARE THREE SPECIES OF ALLIGATOR SNAPPING TURTLES.

A 2014 study trisected the Macrochelys genus. For over a century, naturalists thought that there was just a single species, Macrochelys temminckii. Closer analysis proved otherwise, as strong physical and genetic differences exist between various populations. The newly-christened M. suwanniensis and M. apalachicolae are named after their respective homes—namely, the Suwannee and Apalachicola rivers. Further west, good old M. temminckii swims through the Mobile and the Mississippi.

7. THANKS TO A 19TH CENTURY POLITICAL CARTOON, COMMON SNAPPING TURTLES ARE ALSO KNOWN AS "OGRABMES."

Drawn by Alexander Anderson, this piece skewers Thomas Jefferson’s signing of the unpopular Embargo Act. At the president’s command, we see a snapping turtle bite some poor merchant’s hind end. Agitated, the victim calls his attacker “ograbme”—“embargo” spelled backwards.

8. ALLIGATOR SNAPPERS ATTRACT FISH WITH AN ORAL LURE …

You can’t beat live bait. Anchored to the Macrochelys tongue is a pinkish, worm-like appendage that fish find irresistible. Preferring to let food come to them, alligator snappers open their mouths and lie in wait at the bottoms of rivers and lakes. Cue the lure. When this protrusion wriggles, hungry fish swim right into the gaping maw and themselves become meals.

9. … AND THEY FREQUENTLY EAT OTHER TURTLES.

Alligator snappers are anything but picky. Between fishy meals, aquatic plants also factor into their diet, as do frogs, snakes, snails, crayfish, and even relatively large mammals like raccoons and armadillos. Other shelled reptiles are fair game, too: In one Louisiana study, 79.82% of surveyed alligator snappers had turtle remains in their stomachs.

10. YOU SHOULD NEVER PICK A SNAPPER UP BY THE TAIL.

Ideally, you should leave the handling of these guys to trained professionals. But what if you see a big one crossing a busy road and feel like helping it out? Before doing anything else, take a few moments to identify the turtle. If it’s an alligator snapper, you’ll want to grasp the lip of the upper shell (or “carapace”) in two places: right behind the head and right above the tail.

Common snappers demand a bit more finesse (we wouldn’t want one to reach back and nip you with that long, serpentine neck). Slide both hands under the hind end of the shell, letting your turtle’s tail dangle between them. Afterwards, clamp down on the carapace with both thumbs.

Please note that lifting any turtle by the tail can permanently dislocate its vertebrae. Additionally, remember to move the reptile in the same direction that it’s already facing. Otherwise, your rescue will probably turn right back around and try to cross the road again later.